A strobe zoom device of an electrically driven feed screw type is known in which a light source box disposed in a casing so as to be movable in a fore and aft direction is caused to move in the fore and aft direction by an electrically driven feed screw mechanism to vary a distance along an optical axis between the light source box and a lens disposed in front of the light source box, thereby to vary an illumination angle of strobe light (strobe illumination angle) illuminated onto an object to be imaged.
In the strobe zoom device of the electrically driven feed screw type, a feed screw rod is rotatably mounted to the casing, a female screw member is mounted to the light source box, and a screw thread formed in the female screw member is in threaded engagement with a screw groove formed on the outer circumference of the feed screw rod, whereby a zoom operation is performed when the light source box is moved in the fore and aft direction in response to linear movement of the female screw member caused by rotation of the feed screw rod.